Weeds are plants that grow in an environment where they are unwanted or where they compete with other plants like cultivated crops or native plants. Weed invasions can be very unsightly, threatening tourism and recreation and also cause damage to agriculture. Weeds in some instances provide harbour for pest animals and outcompete native plants which are vital to maintaining the established balance of the natural ecosystem.
What is a noxious weed?
Noxious weeds are plants that are declared by the NSW Department of Primary Industries. Declared plants often have the potential to seriously effect human health, agriculture, recreation or the environment. There are 125 species of weeds that are declared noxious within the Campbelltown Local Government Area. Council manages weed incursions within the area through delivery of its Noxious Weed Management Strategy(39MB, PDF).
Noxious weeds on residential properties
Residents are required under the Noxious Weed Act 1993 to manage noxious weeds on their property. Council conducts regular inspections of private property to assist in educating the community and reducing weed populations. If you would like any advice regarding weed control methods you can contact Council's Environment Unit on 02 4645 4601.
For a full list of Campbelltown’s noxious weeds, their class and legal requirements, visit the Department of Primary Industries website.
New NSW DPI WeedWise Smart Phone App
In March 2015 the NSW Department of Primary Industries released NSW WeedWise, a smart phone app that provides weed profiles for more than 300 noxious and environmental weeds effecting or threatening NSW.
The app provides all of the legal control requirements for noxious weeds as declared under the Noxious Weeds Act 1993, physical descriptions of weeds including images, information about potential impacts, methods of spread and preferred habitat.The app also provides latest control options, registered herbicides for treatment including application rates and techniques as well as the ability to directly report sightings of high priority weeds via email or SMS to the NSW DPI.
Campbelltown’s most unwanted
Do you have any of Campbelltown's most unwanted weeds in your garden? Help look after the local environment by managing these pesky plants on your property.
If you spot any of the below weeds in your garden or in your neighbourhood, please report online or contact Council immediately on 02 4645 4601.
Boneseed (Chrysanthemoides monilifera ssp. monilifera)
Boneseed is listed as a class 1 noxious weed and has the ability to aggressively invade native bushland in Sydney. Its vigorous growth and ability to spread quickly allows it to outcompete native species. It can grow in a range of habitats including dunes, mallee, open woodlands and sclerophyll forests, preferring winter rainfall regions. Boneseed is an erect shrub that grows up to three meters; leaves are 3-9cm long and flowers are yellow with 5-9 petals. In the Campbelltown area scattered infestations have been found and without effective control, Boneseed has the potential to become more abundant and rapidly spread into new areas.
Kei Apple (Dovyalis caffra)
Kei Apple is a drought and frost hardy shrub from southern Africa that has recently been found with the Campbelltown area. The plant itself is usually 3-5m in height with green waxy leaves that are 2-5cm long and 1-3cm wide with large spikes that are up to 7cm in length. The bark is light grey in colour and and the plant produces fruits that are bright yellow or orange and 2.5-4cm in diameter. If left untreated, Kei Apple has the potential to impact many of our significant bush land areas.
Water Lettuce (Pistia stratiotes)
Water lettuce is a free floating aquatic plant with an appearance like an open head of lettuce, and can often grow up to 15 cm tall and 30 cm wide. Water Lettuce is fast growing and has the potential to suffocate waterways by removing oxygen, leaving disastrous conditions for aquatic life. Campbelltown’s waterways are currently free of this weed, however it was recently been found being sold at local markets and in a number of resident’s backyard ponds. If released into the environment, one small specimen has the potential to spread throughout an entire catchment very quickly.
Salvinia (Salvinia molesta)
Salvinia is one of the biggest threats to our waterways in southwest Sydney because of its quick growth and ability to spread through waterways, choking out sub-surface aquatic wildlife and vegetation. Dense infestations greatly restrict river navigation, fishing and recreation, reduce water quality and harbour diseases. Salvinia spreads vegetatively, meaning only small fragments of the plant are necessary for sprouting new growths. Coverage of the plant can double in just 5-10 days! Mechanical removal might be ineffective and in fact greatly worsen the problem, as it breaks up the vegetative material, thereby increasing the number of reproducing plants.
Pampas Grass (Cortaderia species)
Pampas grass can be found in a range of different areas including open grassland, damp alluvial soils and disturbed landscapes. It is a robust, long-lived and forms a large tussock, approximately 1–1.5m across. Flowers are plumed and produce large amounts of wind dispersed seed, which enable it to spread quickly. Pampas grass has become a major threat to bushland areas in and around Sydney and the Central Coast.
Alligator Weed (Alternanthera philoxeroides)
Alligator Weed is possibly Australia's greatest aquatic weed threat, as its rapid spread causes it to choke inland rivers and irrigation systems, restricting water flow, increasing sedimentation and the build up of debris and even encouraging flooding. Alligator weed spreads rapidly by floods, birds and animals, as well as human activities. Small pieces of the weed can be carried to other areas or waterways through machinery or equipment, introducing it to previously unaffected habitats. Once Alligator weed is established on land, it is often nearly impossible to control.
Primrose Willow (Ludwigia peruviana)
This persistent perennial favours creek lines, ponds and silted banks, making it a threat to tributaries of our Georges and Nepean Rivers. It spreads rapidly in waterways through water flow, vegetatively by broken branches, and between waterways through water birds. Individual plants should be manually removed, taking care to remove the roots.
Privet (Ligustrum lucidum and Ligustrum sinense)
Both broad-leaf and small-leaf privet are known to be toxic to horses and their pollen can cause asthma and eczema in humans. They are distinguishable by their purple berries during autumn and individual plants can produce over one million berries per year. These berries are consumed by birds who effectively spread the associated seed within their droppings across the environment including nature reserves and other gardens. In addition Privet trees compete with desirable and native plants for water, nutrients and space and can live up to 100 years. Hand removal of small seedlings and cut/paint stump and drill/fill stump methods for large plants are effective for treatment of the African Olive.
African Olive (Olea europaea ssp. cuspidata)
African Olive is a medium-sized tree that was introduced into Australia in the early 1800's as a hedge plant and as a rootstock for edible Olive varieties. The plant itself has small black fruits and narrow shaped leaves that are 5-10cm long, up to 2cm wide with dark green on the upper surface and yellowish-brown on the lower surface. African Olive thrives on clay soils and one mature plant can produce up to 25,000 seeds in a single season making it a huge threat to local bushland in particular Cumberland Plain Woodland found in areas to the west of Campbelltown. As with Privet, fruits are consumed by birds who effectively spread the associated seed within their droppings across the environment including nature reserves and other gardens. Hand removal of small seedlings and cut/paint stump and drill/fill stump methods for large plants are effective for treatment of the African Olive.
Blackberry (Rubus fruticosus)
Blackberry is an intrusive, thorny, trailing plant, considered noxious in all Australian states. It competes with native species and sown pastures, forming a dense canopy which becomes a fire hazard and harbours pest animals like rabbits and rats. A combination of manual (or mechanical) removal and chemical control is most effective for large infestations.
African Boxthorn (Lycium ferocissimum)
First introduced as a hedge plant, this South African bush forms dense thickets and reduces grazing land areas. Spread by birds and animals who feed on the fruit, this beastly bush plants its roots in deep, leaving broken pieces in the soil from which new plants can spring. For this reason, bushes can be physically removed, but follow up treatment with herbicide is often required.
Lantana (Lantana camara)
This once innocently concealed garden plant escaped and thrived so vigorously that it is now considered one of Australia's most noxious weeds. It can grow in nearly any environment, including along roadsides, fence lines, bushland, and neglected areas of cultivated land. It often grows in inaccessible areas, making removal difficult. Mature Lantana shade other plants and compete with them for moisture because of their shallow spreading root system. Lantana can be poison to cattle and sheep. Despite the damage it causes, Lantana is still widely sold in nurseries. It is spread by birds and reshooting stems. Mechanical or manual removal can be effective for smaller infestations, where chemical follow up may be necessary for larger ones.
Water Hyacinth (Eichhornia crassipes)
Originally an ornamental plant, Water Hyacinth has become a serious aquatic weed threat in Australia. Its free-floating, mat-forming tendency reduces the amount of light available and lowers oxygen levels, affecting water quality and choking out plants and aquatic wildlife. A single plant can reproduce to cover 600m2 in a year. Like other aquatic weeds, Water Hyacinth is extremely difficult to manage as it spreads vegetatively. Small infestations in contained water bodies like dams can be cleared but it is essential that all material is removed or regrowth will occur. In larger water bodies or rivers, mechanical/manual removal may need to be followed up with chemical/biological control, however please contact Council if you have found Water Hyacinth on or near your property before you attempt to remove it; it is an offence to spray chemicals on or near waterways without a licence.
Morning Glory (Ipomoea indica)
A scrambling climber, this garden escapee fares well in urban and bushland areas, often inhabiting moist, sheltered areas along drains and creek lines. A quick spreader, this vine is commonly spread through the dumping of garden waste. Small populations of the vine can be hand removed by gently pulling up the runners, taking care to remove all horizontal stems, as fragments will regrow.
Madeira Vine (Anredera cordifolia)
This climbing vine prefers damp, fertile soils and creek lines. It spreads quickly by entwining its stems around any nearby structure, dropping tubers which emplant beneath the soil. In bushland the vines engulf native species, cutting off light availability for lower sprouting plants. Removal by hand of tubers and seedlings can be successful, while herbicide can be applied by stem-scrape method.
Bridal Creeper/Baby Smilax (Asparagus asparagoides)
This common garden escapee is a major weed of the Cumberland Plain. A ferocious scrambling herb, Bridal Creeper kills native plants by overgrowing them and cutting off sunlight. It is spread by birds who eat the fruit and drop seeds elsewhere, often long distances from the parent plant. Local spread occurs from shoots forming on tubers or when rhizomes are severed and removed. Seeds will germinate year-round. Plants can be dug out and removed, however care must be taken to remove all remaining rhizomes.